Multi-layer concrete ceiling structure comprising a pipe system

ABSTRACT

The invention relates to a concrete ceiling structure having a multi-layer design and comprising pre stressed elemental plates ( 10 ) for absorbing tensile stress, and at least one layer of cast-in-place concrete ( 50 ), especially reinforced concrete, arranged on the plates and used to absorb compressive stress. A pipe system ( 40 ) for the circulation of a fluid, especially air, is built into the structure, for heating or cooling. The pipes ( 40, 140, 240 ) are arranged in the cast-in-place concrete layer ( 50 ), above the elemental plates ( 10 ).

The invention relates to a concrete floor construction having a multilayer structure, containing prestressed element slabs for accommodating tensile stresses and at least one layer of cast-in-place concrete located over it, especially reinforced concrete, for accommodating compression stresses.

In industrial, commercial and residential construction the floors of stories widened are necessary for large spans. Especially in the construction of office buildings is component activation questioned so that in many cases the widely spanned floors are no longer suspended, but the bottom of the concrete after troweling and painting is finished so that corresponding heat radiation can take place.

Concrete floor constructions are known which have a multilayer structure and which are formed from pretensioned element slabs and from a layer of cast-in-place concrete located over it. The disadvantage in this connection is that the spans in these known constructions are limited to roughly 10 to 12 meters. Furthermore, in the known constructions it is disadvantageous that component activation, i.e. use of the floor surface by heating or cooling for climate control of the underlying space, is not possible.

The object of the invention is to develop a concrete floor construction of the aforementioned type such that the concrete floor construction allows large support widths for a minimum thickness of the total construction, i.e. especially an office building or the like, to build from outside wall to outside wall without intermediate support and furthermore to make it possible to use the floor by component activation by heating or cooling for climate control of the underlying space.

This object is achieved as claimed in the invention by a concrete floor construction as claimed in claim 1.

Because a pipeline system for routing-through of a fluid, especially air, is integrated for heating or cooling, the pipelines being located in the layer of cast-in-place concrete over the element slabs, it is possible to route heated or cooled air for heating or cooling of the concrete floor construction through the pipelines and in this way to cool or heat the entire concrete floor construction for climate control of the underlying space. Furthermore, it is advantageous that because the pipeline system is located in the layer of cast-in-place concrete over the element slabs, the specific weight per square meter of floor surface is reduced by the concrete displaced by the pipeline in the layer of cast-in-place concrete without adversely affecting the strength of the concrete floor construction, since underneath the pipelines prestressed element slabs are located for accommodating the tensile stresses and the layer of cast-in-place concrete which is located over the prestressed element slabs and in which the pipelines of the pipeline system are located is suitable for accommodating compression stresses. In this way it is possible to achieve a support width of up to 16 meters at a total floor thickness of 40 cm.

The inserted pipes which can be used at the same time for transport of a fluid, preferably air, for component activation greatly reduce the floor weight, by which both sagging and also amounts of reinforcement can be reduced.

Other advantageous embodiments of the invention are given in the dependent claims.

Thus it is especially advantageous when the pipelines are located in the region of the neutral fibers of the concrete floor construction.

Due to the arrangement of the pipelines in the region of the neutral fibers of the concrete floor construction, i.e. in that region in which the concrete floor construction experiences neither compression nor elongation as a result of sagging due to weight, on the one hand the integrated pipeline system is not mechanically stressed and on the other by the arrangement of prestressed element slabs for accommodating the tensile stress underneath the pipelines and of cast-in-place concrete for accommodating compression stresses the entire concrete floor construction is mechanically optimized. The layer of cast-in-place concrete is arranged here such that it surrounds the pipeline system which is integrated into the concrete floor construction and also extends above the integrated pipeline system for accommodating compression stresses.

Preferably between the prestressed element slabs and the cast-in-place concrete there are lattice beams and/or compound elements. In this way adhesion between the prefabricated slab and the cast-in-place concrete is produced.

In one preferred embodiment the pipelines have a profiled surface and/or reinforcements located on the pipe surface and which form adhesion with the cast-in-place concrete and especially supplement or replace the lattice beams in regions. The laterally profiled pipes which are placed in the concrete floor construction thus make it possible for the pipes for their part to produce adhesion to the cast-in-place concrete so that at least lattice beams are not necessary in this region.

In the concrete floor construction at least some element slabs have passages through which the pipelines can be routed, especially in the region of each opening there additionally being transverse reinforcements. The pipelines in the prefabricated slab can be supplied through these openings with fluid, preferably air, especially climate-controlled air, or the air can be routed into the space underneath the floor construction to climate-control the space. Since openings in the prestressed concrete slab mean spot weakening of the slab, in this region there are especially additional transverse reinforcements.

Preferably these additional transverse reinforcements are located above the element slab, especially additional transverse reinforcements in the region of the passages in the element slabs for routing pipelines being located above the element slab. These transverse reinforcements can be arranged such that they are not located on the element slab, but are connected to one another by way of a loop construction by overlapping walls. The transverse reinforcement additionally enables plate action of the overall construction. This enables the most varied architectonic interests to be satisfied so that the most diverse supports of the floor construction are possible.

In one preferred embodiment the pipelines, especially in the region in which a pipeline passes through the element slab, are made with an oval or rectangular cross section, especially the longer axis of symmetry being aligned in the direction of primary tensile stress.

The arrangement of an oval or rectangular pipe results in that the pipe itself acts as a type of beam which has already been installed in the prefabricated part. In installation the pipe acts like a beam by stiffening and establishes the adhesion. To prevent the prestressing from being transmitted to the pipe, at certain intervals corrugated intermediate pieces can be arranged which prevent transmission of the prestressing force to the pipe. Due to this pipe arrangement with an oval or rectangular cross section such that the longer axis of symmetry is aligned in the direction of the main tensile stress, different buckling and bending strength in the direction of the two axes of symmetry of a non-round pipe can be made advantageously useful by the pipe itself acting as the beam and contributing to the strength of the component.

Preferably the ends of the pipeline which lead through the element slabs to the vicinity can be closed by means of openable and/or removable flaps or the like. The arrangement of flaps or the like enables cleaning of the pipeline system, especially also maintenance of the pipeline system.

Preferably the element slabs are made of high-strength concrete. Preferably the element slabs have a thickness of at least 8 cm, preferably 10 cm or 12 cm.

By using high-strength concrete and/or a thickness of at least 8 cm for the element slabs a concrete floor construction with very high strength and bearing capacity is devised which allows large support widths of the overall construction.

Preferably the element slabs have transverse reinforcements which in the transverse direction of the element slabs form lateral overlaps and/or overlaps pointed obliquely upward which form adhesion with the cast-in-place concrete in order to accommodate stresses of the secondary bearing direction. This protects against crack formation in the transverse direction. In particular in the transverse direction very strong adhesion between the prestressed element slabs and the cast-in-place concrete is established.

To the extent piping of the concrete floor construction is omitted in the edge region, i.e. that the pipeline system located above the prestressed element slabs is formed in its three-dimensional extension to one middle region of the concrete floor construction while maintaining a distance to the edge region, it becomes possible to enable support of the concrete floor construction in any bearing situations.

Three exemplary embodiments of the invention are shown in the figures and are detailed below.

FIG. 1 shows a perspective view of a first embodiment of the invention (partially completed),

FIG. 2 shows a top view of an element slab with a pipeline system located over it according to the embodiment from FIG. 1,

FIG. 3 shows a prestressed element slab in a bottom view,

FIG. 4 shows the section IV-IV as shown in FIG. 2,

FIG. 5 shows the section V-V as shown in FIG. 2,

FIG. 6 shows a top view of a prestressed element slab with a pipeline system of a second embodiment of the invention located over it,

FIG. 7 shows the section VII-VII as shown in FIG. 6,

FIG. 8 shows a section through a third embodiment of the invention.

FIG. 1 shows a perspective view of the concrete floor construction in the partially completed state which is formed in its bottom region by prestressed element slabs 10. The element slabs 10 are equipped with compound elements 20 and lengthwise and transverse reinforcements which are not visible in this perspective. On the lengthwise edges the prestressed element slabs 10 for producing adhesion have loops 30 which are pointed obliquely up and which are arranged in alternation, as shown in FIG. 1. These loops 30 and the lengthwise aligned compound elements 20 form a composite with cast-in-place concrete which has not yet been applied in FIG. 1. For this purpose the loops 30 are made such that they form laterally projecting overlaps 30 which are pointed obliquely up over the lengthwise edge of the element slab in order to accommodate stresses of the secondary bearing direction.

Above the prestressed element slabs 10 there are pipelines 40 which form a pipeline system for routing a fluid through for component activation. Heating/cooling of the space under the concrete floor construction can thus take place by this thermal component activation. For purposes of removing air from the underlying space or feeding air into the underlying space, the pipeline system is connected to the underlying space by way of connecting elements 41 which lead through passages in the element slabs to the underlying space. From the bottom the ends of the pipelines of the connecting pieces 41 leading to the underlying space are closed by means of openable flaps by which maintenance and cleaning of the pipeline system are enabled.

To complete the concrete floor construction as shown in FIG. 1, at this point it is simply necessary to pour a layer of cast-in-place concrete which surrounds the pipelines 40 and forms bearing adhesion by means of the loop-shaped overlaps 30 and the compound elements 20.

The pipelines 40 of the embodiment of the invention as shown in FIG. 1 have a round cross section.

It is especially advantageous that several advantages are achieved by the concrete floor construction as claimed in the invention, which of prefabricated and prestressed element slabs 10, pipelines 40 located over the element slabs 10, and a layer of cast-in-place concrete which is to be poured on site and which surrounds and covers the pipelines 40 and forms adhesion to the elements slabs [sic]. Thus, on the one hand the statics of the concrete floor construction is ensured in that there are prestressed element slabs 10 for accommodating tensile stresses and a layer of cast-in-place concrete located above the element slabs 10 for accommodating compression stresses, component activation of the concrete floor construction being enabled by the integrated pipeline system. At the same time, the concrete floor construction becomes lighter by the integration of the pipelines 40 around the cast-in-place concrete displaced by the pipelines 40. As a result of this reduction of the mass per square meter of the concrete floor construction larger spans than in conventional concrete floor constructions which have a multilayer structure is enabled. At the same time component activation of the concrete floor is possible.

In the embodiment as shown in FIG. 1, the pipelines 40 are located in the region of the neutral fibers of the concrete floor construction, i.e. that in the completed concrete floor construction the element slabs 10 are loaded in tension and the layer of cast-in-place concrete which is not shown and which covers and surrounds the pipelines 40 above the element slabs 10 is loaded in compression, the pipelines 40 not being exposed to mechanical loading by their being located in the region of the neutral fibers of the concrete floor construction.

FIG. 2 shows a top view of a prestressed element slab 10 with pipelines 40 of the embodiment as shown in FIG. 1 located above it. The element slab 10 is equipped with compound elements 20 pointed lengthwise and has passages into which the connecting pieces 41 of the pipelines 40 can be inserted, by means of which a connection of the pipelines 40 to the space which lies under the element slab 10 is formed.

FIG. 3 shows a bottom view of an element slab 10 with loop-shaped overlaps 30 along the lengthwise edges of the element slab 10 and the transverse reinforcements 25 which are indicated by the broken line and which are placed in the element slab 10. The loop-shaped overlaps 30 are arranged such that they engage one another in alternation with a further element slab located laterally next to the element slab 10. In order to ensure optimum application of force and adhesion to the cast-in-place concrete, the transverse reinforcements 25 on the edge of the element slab 10 are made in the form of loops 30, i.e. the loops 30 and the transverse reinforcement 25 are components of the same lattice beam.

The element slab 10 has several passages 11 to which the connecting pieces 41 of the pipelines 40 located above the element slab 10 can be connected.

FIG. 4 shows the section IV-IV according to FIG. 2 and by way of extract, enlargements of details A and B. The concrete floor construction is formed by prestressed element slabs 10 with prestressing steel 35. Above are pipelines 40 and compound and shear reinforcements 15. Likewise above the element slab 10 are reinforcements 45 which form adhesion with the cast-in-place concrete 50. The cast-in-place concrete 50 surrounds the pipelines 40 and forms adhesion with the reinforcements 45 and the compound or shear reinforcement 15.

Detail A shows the support of the concrete floor construction as claimed in the invention on one side wall 60 on which the element slab 10 partially rests. The element slab 10 which contains the prestressing steel 35 has a passage 11 for holding the pipeline connecting piece 41 to the connection to the pipeline 40.

Laterally and above the element slab 10 there are reinforcements 45 which form adhesion with the cast-in-place concrete 50. Both the element slab 10 and also the finished cast-in-place concrete 50 form the support on the side wall 60.

Detail B shows in an enlarged cross section the middle region of the concrete floor construction with element slabs 10, pipelines 40 and reinforcements 45. The layer of cast-in-place concrete containing the reinforcements 45 and surrounding the pipelines is not shown in this representation.

A reversing box 44 is connected to the pipeline 40. The pipeline system has a feed 42 and a return 43 and is connected by way of this feed 42 and return 43 to a climate-control device for component activation, i.e. for heating or cooling.

FIG. 5 shows the section V-V as shown in FIG. 2. The element slabs 10 contain integrated prestressing steel 35, transverse reinforcements 25 to whose end the overlaps 30 which are made loop-shaped are connected, and compound elements 20 which run in the lengthwise direction of the element slab 10. The overlaps 30 are set at an angle of 30 degrees against horizontal and extend laterally and obliquely up from the element slab 10 in the direction of the next element slab which lies next to it along the lengthwise edge. These overlaps 30 made in a loop shape form adhesion with the cast-in-place concrete 50. Above the element slabs 10 are the pipelines 40 which are completely surrounded by the layer of the cast-in-place concrete 50. Adhesion of the concrete floor construction is established by way of loops 30 and the compound elements 20 which extend between the pipes 40 in the lengthwise direction.

FIG. 6 shows a second embodiment of the invention in a top view of an element slab 10 (the same reference numbers label the same parts as before) with compound lattice elements 20 and with pipelines 140 which are located above the element slab 10 and which are connected by way of the corresponding connection pieces 141 through passages in the element slabs 10 to the vicinity.

FIG. 7 shows the section VII-VII as shown in FIG. 6. The element slabs 10 have a structure which is identical to the previous embodiment as shown in FIGS. 1 to 5. Above the element slabs 10, within the layer of cast-in-place concrete 50, there are pipelines 140 which have a cross section which is formed from two vertical side walls, the top and bottom of the pipelines 140 being formed by arcs. The vertically standing side walls of the pipeline 140 align the longer axis of symmetry of the pipelines 140 in the direction of primary tensile stress, i.e. that the pipeline 140 due to the composition of its cross section assumes a bearing function in the concrete floor construction.

FIG. 8 shows a section through a third embodiment of the invention. Above the prestressed element slabs 10 there are pipelines 240 which are covered and surrounded by a layer of cast-in-place concrete 50. The pipelines 240 have a rectangular cross section, the longer axis of symmetry of the rectangular cross section being perpendicular and thus the side walls of the pipelines contributing to the statics of the floor construction. 

1. Concrete floor construction having a multilayer structure, containing prestressed element slabs (10) for accommodating tensile stresses and at least one layer of cast-in-place concrete (50) located over it, for accommodating compression stresses, characterized in that a pipeline system (40) for routing-through of a fluid, is integrated for heating or cooling, the pipelines (40, 140, 240) being located in the layer of cast-in-place concrete (50) over the element slabs (10), between the prestressed element slabs (10) and the cast-in-place concrete (50) there are adhesion members selected from the group lattice beams, compound elements, and combinations thereof (15, 20, 30).
 2. Concrete floor construction as claimed in claim 1, wherein at least one layer of cast-in-place concrete is reinforced concrete and further wherein the pipelines (40, 140, 240) are located in the region of the neutral fibers of the concrete floor construction.
 3. Concrete floor construction as claimed claim 2, wherein the pipelines (40, 140, 240) have a profiled surface or reinforcements on the pipe surface for providing adhesion with the cast-in-place concrete (50).
 4. Concrete floor construction as claimed in claim 2, wherein at least one element slabs (10) has passages (11) through which the pipelines (40, 140, 240) can be routed, further wherein the region of each opening (11) has transverse reinforcements.
 5. Concrete floor construction as claimed in claim 4, wherein the transverse reinforcements, in the region of the passages (11) for routing pipelines (40, 140, 240) are located above the element slab (10).
 6. Concrete floor construction as claimed in claim 2, wherein the pipelines (40, 140, 240), especially in the region in which the element slab (50) passes through, have an oval or rectangular cross section, especially the longer axis of symmetry being aligned in the direction of primary tensile stress.
 7. Concrete floor construction as claimed in claim 1, wherein the pipelines (40, 140, 240) have pipeline ends (41) which lead through the element slabs (10) can be opened or closed by means of openable or removable means of selected from the group comprising flaps, valves, plates and seals.
 8. Concrete floor construction as claimed in claim 1, wherein the element slabs (10) are made of high-strength concrete.
 9. Concrete floor construction as claimed claim 1, wherein the element slabs (10) have a thickness of at least 8 cm, preferably 10 cm or 12 cm.
 10. Concrete floor construction as claimed in claim 1, wherein the element slabs (10) have transverse reinforcements (25) which in the transverse direction of the element slab (10) form lateral overlaps and/or overlaps (30) which are pointed obliquely upward and which form adhesion surfaces for to the cast-in-place concrete (50) in order to accommodate stresses of the secondary bearing direction. 